Hongbo Lu

Organic optoelectronic synaptic devices have attracted considerable attention for applications in neuromorphic vision systems. However, most reported devices operate with fixed response modes, which limits their adaptability to complex and dynamic lighting environments and thereby restricts their applications in dynamic visual information processing and environmental adaptation. In particular, background light is typically regarded only as an external environmental factor rather than as a key variable for modulating device response modes. Here, an ambient‐light‐modulated biomimetic synaptic transistor incorporating Au nanoparticles into the semiconductor layer is reported. The device exhibits environment‐dependent switching between excitatory and inhibitory photocurrent responses to the same optical signal under different background light conditions, thus producing reconfigurable photoresponse behavior. Leveraging this bidirectional photoresponse, the device achieves reliable color and digit recognition under variable ambient illumination. This background‐light‐mediated reconfiguration of synaptic behavior enables dynamic reconstruction of visual perception and behavioral decision‐making, while mimicking environmentally adaptive visual behaviors observed in biological systems. Moreover, through circuit design and system‐level integration, a closed‐loop pathway of “environmental adaptation–response adjustment–behavioral decision reconstruction” is established. This work provides a practical strategy for developing optoelectronic neuromorphic devices with high environmental adaptability.

A method for the fabrication of low-scattering liquid crystal (LC) photonic devices, including a Fresnel zone plate (FZP) and grating, was proposed. The core of this method lies in doping the alignment layer with a photoinitiator, followed by the generation of polymer brushes via surface-initiated polymerization (SIP) technology. This technology effectively fixes the tilt angle of LC molecules under saturation voltage, resulting in the formation of a stable structure characterized by the alternating distribution of twisted nematic and vertically aligned regions within the twist nematic (TN) type of LC cells. Compared with conventional methods that rely on polymer networks to stabilize the tilt angles of LC molecules, this approach significantly mitigates scattering caused by refractive index mismatches between the polymer network and the LC material. Owing to its low scattering property, the fabricated binary FZP achieved a diffraction efficiency as high as 35.3%, and the haze is only 8.6%. The fabricated amplitude grating has a contrast ratio as high as 625 and a haze of only 14.1%. The proposed method enables the rapid and efficient production of low-scattering LC devices, demonstrating great application potential in photonic device fabrication.

1. As energy consumption continues to rise in the construction and transportation sectors, smart window technology has become an important focus of energy conservation research [1–5]. Among various...

An HTPDMS-modified MF shell deforms cholesteric liquid crystal microcapsules from spheres into oblate spheroids. This shape change expands their reflective area from points into circular regions, significantly increasing overall reflectivity.

Polyvinyl chloride (PVC) gel is a soft and highly transparent electroactive polymer. Compared to liquid crystal lenses and liquid lenses, PVC gel-based lenses offer advantages such as compactness, polarization independence, and immunity to gravity effects. These characteristics make them highly promising for applications in imaging, sensing, optical communication, biomedical engineering, and displays. However, their practical use has been limited by the high driving voltage required. This work investigates the influence of doping PVC gels with ionic liquids (ILs) of varying content and anion-to-cation volume ratios on the performance of PVC gel-based lenticular microlenses (LMAs). For a pitch of 60 μm, doping small amounts of ILs reduces the driving voltage from 50 V to below 10 V. Additionally, the response time can be shortened by lowering the surface energy of the substrate. The optimized PVC/IL gel-based LMA has been successfully applied to a 2D/3D switchable display. By adjusting the voltage to control the focal length of the PVC/IL gel-based LMA, displays with different viewing angles can be achieved.

reconfigurable intelligent surface (RIS) have received significant attention in the field of communication and wireless networks, due to their numerous advantages, such as low cost, low energy consumption, miniaturization, programmability, and ease of deployment. This article proposes an RIS based on liquid crystal (LC) for constructing wireless communication systems. Tunable LC embedded between metal microstructures supported by quartz substrates allows for precise control of the reflected wave phase. The experimental results demonstrate that RIS has more than 360° of phase modulation capability and four stable digital coding states at the optimal operating frequency of 100.2 GHz. In addition, the RIS has a 100° beam scanning capability, providing a solid foundation for tracking and targeting during communications. The communication capability of RIS was then demonstrated in the sub-terahertz band by constructing a 16QAM constellation diagram test system and a video real-time transmission system with varying deflection angles. Our work provides excellent solutions for communication and wireless network applications in the millimeter wave and terahertz (THz) frequency bands.

In this study, thermochromic microcapsules with excellent optical properties were fabricated by combining stepwise heated interfacial polymerization and pre-alignment in the smectic phase, and coatings with high reflectivity were achieved.

Nonmechanical fast response optical beam steering technology is increasingly essential for telecommunications, imaging systems, optical sensing, displays, and military applications. Polymer network liquid crystal (PNLC) beam steering can achieve submillisecond response times but faces limitations due to scattering issues arising from the refractive index mismatch between the polymer network and the liquid crystals (LCs). In this article, we demonstrate a scattering-free, fast-response LC beam steering by using polymer brushes to stabilize the gradient refractive index. First, the initiator is incorporated into the alignment layer and the monomer is mixed into the LC layer. Surface-initiated polymerization (SIP) is then employed to grow the polymer brushes exclusively on the substrate's surface, thus confining the polymer network's growth to the LC bulk and reducing interfacial scattering. For polymer brush stabilized liquid crystal (PBSLC) beam steering device with a period size of 225 μm and a cell gap of 7.2 μm, the average transmission rate reaches 88% in the visible light spectrum with a haze value of only 6.91. The steering angle is 0.16, and the diffraction efficiency is 80.3%. When a voltage of 35 V_rms is applied, the primary energy can be tuned to the zeroth order, with a response time close to 1 ms. By cascading two PBSLC beam steering devices with opposite steering directions, the primary energy of the beam can be adjusted between zeroth, +1, and -1 order. This method requires only a UV light source, a precision displacement stage, a power supply, and a mask, avoiding the need for expensive equipment and complex electrode fabrication. By adjustment of the phase change period, step width, and number of steps during fabrication, the steering angles and diffraction efficiency of the PBSLC beam steering device can be easily controlled, highlighting its significant potential for industrial production.